The Swansea City midfielder will and his older brother Martin will become the first siblings to take part in both formats of the Games in the same year for Great Britain
The pair will be the first siblings in British history to compete in the Olympic and Paralympic Games in the same year.
Sinclair will be playing for Stuart Pearce's men's football side while his brother will compete for Great Britain's cerebral palsy seven-a-side football team at the Games.
Martin also suffered from a misdiagnosed hip injury that consigned him to a wheelchair for three years and Sinclair has spoken of his admiration for his brother.
"I'm more proud of him than he is of me, definitely," Scott told reporters. “And he’s more critical of me than I am of him, too.
"He's been through so much in his life. Being in a wheelchair for two or three years after breaking his hip and then being misdiagnosed by the doctors was a lot to go through.
"My mum and dad were stretching him out every day [believing it was a ligament injury and] not realising he had a broken hip."
The midfielder also spoke of how Martin keeps him level-headed and helps take the pressure off him and was happy to see his brother receive the attention he deserves.
"So he keeps me level-headed, keeps my feet firmly on the floor," he explained. "If I'm having a hard time, if I'm not scoring, it helps that I realise it’s not all about me.
"With the pressures of football not scoring seems like the end of the world but one phone call to my brother puts things in the right place. It helps me see football in perspective.
"I'm happy to take the second seat here. It's all about my brother and what he's been through. It kills you at times and I'll never really know how he coped with it but he is amazing.
"I'm just so happy for him, it's nice for him to take the spotlight and be able to tell his story."